"Upon completion of all sections on the MCAT, test-takers are given the option to either submit or void their scores. While the thought of voiding your scores after weeks or months of preparation may be unimaginable, certain circumstances should prompt consideration of this option. If you do choose to void your scores after a poor exam session, medical schools will not receive any record of your exam.
No scores are issued for voided tests, and if you do not have any other MCAT scores, you will have to sit for the test again in order to apply to medical school. Choosing to void your scores should therefore be done cautiously, and these three scenarios may be appropriate reasons not to submit your exam on test day." …